"Note that the crazy 61A figure " -- yes, I've learned that amp rating means absolutely nothing!
"The IRFR3708 has a worst-case on-resistance of 0.03 ohms at Vgs=2.8, so at about 5A it will dissipate 0.75W
which is feasible for a large surface mount package. So yes, a good choice."
Great! And I can have a pull down resistor to keep it off during the MCU's startup? 10K??